The present invention is directed to an overhead strapper. More particularly, the present invention is directed to an improved flexible strap feed guide for an overhead strapper.
Strappers are in widespread use to, for example, position and tension strap material around a load. Strapping loads may be done for a number of reasons. Often, loads are strapped in order to facilitate handling and transport.
Many loads that require strapping are large, oversized loads. Loads may also be compressible. For example, the load may be a large stack of cardboard items or a bale of textile material.
In order to accommodate large or oversized loads, overhead strapping machines are used. One exemplary strapper is disclosed and described in pending U.S. patent application Ser. No. 10/999,084 to Ropers et al., in which the size of the strap chute can be varied by raising and lowering a horizontal platen that carries the upper portion of the strap chute. The platen is brought into close contact with the upper surface of a load prior to strapping to reduce the opportunity for strapper malfunction by maintaining the size (height) of the strap chute only to that required to accommodate the load.
Such a strapper includes a frame, an upper horizontally oriented platen mounted to the frame for vertical movement along the frame and a modular strapping head mounted to the platen and movable therewith. A modular feed head is fixedly mounted to the frame, spaced from the strapping head and stationary relative to the platen. A strap guide is mounted in part to the frame and in part to the platen. The strap guide provides a varying length pathway from the feed head to the strapping head.
In this strapper, the strap guide is formed from a plurality of pairs of discrete wall portions (tile-like elements) that move or pivot between a closed configuration to retain the strap within the pathway and an open configuration in which the strap is released from the pathway. The pairs of discrete wall portions are biased inwardly to the closed position. A turning assembly is mounted for movement with the platen and cooperates with the strap guide to redirect the strap as the strap exits from the pathway to the strapping head and an extension portion extends from the turning assembly to the strapping head. The vertical portion of the guide has a varying height strap path dependent upon the vertical position of the upper horizontally oriented platen. The varying height is provided by the discrete wall portions that close to form the strap guide or chute and open to release the strap.
While this arrangement functions well, in certain instances, the height of the vertical guide portion may be to high. That is, there may be instances in which although the elevated strapper height is needed, it may be desirable to lower or reduce the height of the vertical guide portion.
Accordingly, there is a need for an overhead strapping machine that uses a relocated feed head (off of the overhead platen), that incorporates a reduced height required vertical guide portion. Desirably, such a machine includes a simplified flexible guide arrangement that permits varying the height at which the platen can reside during machine operations.